The Dow Jones industrial average plunged 2.54 percent closing down 666 points Friday and suffered its worst week in two years as concerns over rising interest rates and inflation from an overheated economy triggered a long-feared sell-off.

It was the worst day for stocks since President Trump took office and a stark reversal from the optimism that has propelled the markets higher for most of the past year. The stock market has been on a historic nine-year bull run.

The U.S. and world economies are so strong that people think it cannot last. Concerns were fueled by a Labor Department report that wages in January were 2.9 percent higher than a year go and unemployment held at 4.1 percent. A tightening labor market sparked fears that interest rates will rise."